adjusted transparency for dragging sprite icons

src/gui.js

@@ -8118,7 +8118,7 @@ SpriteIconMorph.prototype.prepareToBeGrabbed = function () {
     var ide = this.parentThatIsA(IDE_Morph),
         idx;
     this.mouseClickLeft(); // select me
-    this.alpha = 0.5;
+    this.alpha = 0.85;
     if (ide) {
         idx = ide.sprites.asArray().indexOf(this.object);
         ide.sprites.remove(idx + 1);